NO, although the sixes have the same TYPE of transmission, the internals of such are not as strong as our big brothers. I'm not sure what they are good up to power and torque wise but I know for a fact that a v6 tranny will 'splode in a GT. I was talking with a guy who tunes mustangs as a second job about engine swapping/modding/buy-new-car-ing, etc. I'll take his word for it.